The invention relates to a cutting apparatus for sheet material like paper, particularly as one of several juxtaposed cutting units of a cutting station, with at least one cutting blade mounted so that it can be reciprocated in a cutting movement with respect to a counterblade, the cutting blade being fixed by at least one clamping member in removable manner with one lateral face against a blade support. The apparatus has sides belonging to the lateral faces of the cutting blade and also outsides at right angles thereto formed by end sides belonging to the ends of the cutting blade and a longitudinal side remote from the blade edge.
Such cutting mechanisms are in particular used on production lines for exercise books, writing pads, etc, several juxtaposed, jointly functioning cutting mechanisms cutting individual portions, which then form the finished product, from strips of e.g. wire-stitched, adhesively bound or similar sheet layers. Hitherto in the case of such cutting mechanisms, the cutting blades are fixed in the blade rocker arms provided as the blade supports in such a way that in the blade, having a total length of e.g. approximately 360 mm, there are several tapholes at right angles to the cutting plane, by means of which the cutting blade is drawn against the blade rocker arm by clamp botts and is consequently fixed.
The clamp bolts pass through elongated slots in the blade rocker arm located approximately at right angles to the longitudinal direction of the cutting blade, so that the latter can be adjusted with respect to the blade rocker arm or counterblade in its position at right angles to the cutting edge. In particular with the relatively frequently occurring, relatively small useful widths, in which the cutting mechanisms or cutting blades are correspondingly closely juxtaposed, it is very difficult to obtain access to the clamp bolts, because as a result of the adjacent cutting mechanism they cannot be reached from the side of the mechanism belonging to the lateral face of the cutting blade, although their bolt heads used for actuation or operation are located on the lateral faces of the blade rocker arm. In fact, the clamp bolt heads can only be reached by passing between adjacent cutting mechanism from their end sides and this can be particularly difficult for clamp bolts located in the vicinity of the cutting blade length. The loosening of the cutting blade is relatively difficult and the fixing of a new, sharp cutting blade is even more difficult, because as a result of handling problems both the clamping moment of the clamp bolts can only be uniformly adjusted only with difficulty and the simultaneous adjustment of the cutting blade at right angles to the cutting edge is extremely difficult. Thus, blade changing is very time-consuming in the known cutting mechanisms and this leads to long machine down times. It has e.g. been found that roughly five hours are necessary for changing the blades on six blade rocker arms, which are provided for the simultaneous cutting of five portions.